1. Field of the Invention
The present invention relates to a display device, and more particularly, to an organic light emitting display device.
2. Description of the Related Art
Organic light emitting display devices may deteriorate when moisture permeates into the devices and contacts certain components of the devices. Accordingly, a sealing is required to produce organic light emitting display devices that operate stably and have desired lifetimes.
Conventionally, metal or glass is processed into a cap-like form having a groove, and then the groove is filled with a moisture absorption agent in the form of a powder or film. The moisture absorption agent film is then attached to the groove using a double-sided tape.
Japanese Patent Laid-open Publication No. hei 9-148066 discloses an organic light emitting display device including a stacked structure in which an organic emission material layer formed of an organic compound is interposed between a pair of electrodes that face each other, a sealing container that isolates the stacked structure from an external atmosphere, and a moisture absorption agent, such as alkali metal oxide, alkali-earth metal salt, or the like, inside the sealing container. However, such an organic light emitting display device has a large thickness due to the shape of the sealing container. In addition, although the moisture absorption material exists in a solid state after it absorbs moisture, it is opaque, which is not suitable for a top emission type organic light emitting display device.
U.S. Pat. No. 6,226,890 discloses an organic light emitting display device including a moisture absorption layer formed of a binder and a moisture absorption agent including solid particles having a particle diameter of 0.1 to 200 μm. In this case, however, the organic light emitting display device cannot be applied to a top emission type organic light emitting display device because of its semitransparent or opaque characteristics, and its the moisture absorption capability, color purity, and contrast characteristics are insufficient.